666612 has 18 divisors (see below), whose sum is σ = 1685138. Its totient is φ = 222192.

The previous prime is 666607. The next prime is 666637. The reversal of 666612 is 216666.

It can be written as a sum of positive squares in only one way, i.e., 509796 + 156816 = 714^2 + 396^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a nude number because it is divisible by every one of its digits.

It is a nialpdrome in base 7.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9223 + ... + 9294.

2⁶⁶⁶⁶¹² is an apocalyptic number.

It is an amenable number.

666612 is an abundant number, since it is smaller than the sum of its proper divisors (1018526).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

666612 is a wasteful number, since it uses less digits than its factorization.

666612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18527 (or 18522 counting only the distinct ones).

The product of its digits is 2592, while the sum is 27.

The square root of 666612 is about 816.4631038816. The cubic root of 666612 is about 87.3556586218.

The spelling of 666612 in words is "six hundred sixty-six thousand, six hundred twelve".